1. Field of the Invention
The invention relates to static structures and a method for building same. More specifically, a concrete and wood prefabricated wall unit and method for assembling the wall unit are described.
2. Description of the Prior Art
Prefabricated building units are well known in the prior art. Wooden building parts such as trusses and framed walls are frequently preassembled into a complete structure in a short time. The prefabricated units have the advantage of being designed and assembled under controlled conditions for uniformity of size and high quality.
Concrete wall units are also well known in the prior art, as evidenced by U.S. Pat. No. 1,355,572, which describes a building of concrete slabs held together by tie rods extending through horizontal bores in the slabs. Another prefabricated wall is described in U.S. Pat. No. 3,350,826, which discloses a method of attaching a precast concrete wall to a footing by placing vertical tie rods through bores in the wall and footing, and then grouting the rods in place. U.S. Pat. No. 3,330,084 discloses a wall panel joint cap that holds precast concrete slabs together and provides attachment points for roof trusses. Each of these patents demonstrates the difficulty in easily assembling prefabricated concrete slabs into a finished structure. Furthermore, the structure by which prior art patents suggest assembling the slabs has been precast bores in the slabs through which long tie rods are placed, or alternatively, casting the slabs in special frames that can accomodate long tie rods. Thus, a continuing problem in the prefabricated concrete building art has been to assemble precast slabs with a strong bond homogeneous to the concrete slab.
A further problem is to create an interior coating on the concrete wall that allows insulation and standard interior building apparatus to be applied. Framed walls have natural areas where insulation, plumbing, heating, and electrical connections can be added, but concrete slabs require additional framing on the interior of the building to allow room for needed systems. The exterior of precast slabs also requires added finishing before the building has a finished appearance.